Plug assembly

ABSTRACT

A plug assembly includes an upper cover, a heat-conducting element, a heat-conducting pipe, a circuit board and a lower cover. A rear end of a top of the upper cover is equipped with a plurality of heat dissipation fins. The heat-conducting element includes a first heat-conducting element equipped on a bottom surface of the upper cover, and a second heat-conducting element fastened to a bottom surface of the first heat-conducting element. A top of the first heat-conducting element opens a receiving space. The heat-conducting pipe is received in the receiving space. The heat-conducting pipe extends rearward through a rear end of the receiving space. The circuit board is mounted in the upper cover and contacts with the second heat-conducting element. The lower cover is mounted to the upper cover.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the priorities of U.S. provisional patentapplication No. 62/688,393, filed on Jun. 22, 2018 and Taiwan patentapplication no. 107213211, filed on Sep. 28, 2018, which areincorporated herewith by reference.

BACKGROUND OF THE INVENTION 1. Field of the Invention

The present invention generally relates to a plug assembly, and moreparticularly to a plug assembly with a heat dissipation function.

2. The Related Art

As known, a quad small form-factor pluggable (QSFP) interface isassembled to and contacts with an outer shell. The quad smallform-factor pluggable (QSFP) interface reaches a heat dissipationfunction by virtue of the outer shell cooperating with the QSFPinterface. The outer shell has multiple radiating fins distributed on anexternal surface thereof. When the QSFP interface works, heat energiesgenerated by the QSFP interface working are transmitted to the outershell through a heat conduction way, and then a heat dissipation purposeis reached by use of the radiating fins distributed on the externalsurface of the outer shell.

However, in an aforesaid heat dissipation way, another shell needsassembling to the QSFP interface in addition, and consequently a volumeand a manufacturing cost of the QSFP interface are increased.

Therefore, it is necessary to provide an innovative plug assembly with aheat dissipation function, so that the innovative plug assembly itselfhas a better heat dissipation effect.

SUMMARY OF THE INVENTION

An object of the present invention is to provide a plug assembly. Theplug assembly includes an upper cover, a heat-conducting element, aheat-conducting pipe, a circuit board and a lower cover. A rear end of atop of the upper cover is equipped with a plurality of heat dissipationfins. The heat-conducting element includes a first heat-conductingelement equipped on a bottom surface of the upper cover, and a secondheat-conducting element fastened to a bottom surface of the firstheat-conducting element. A top of the first heat-conducting elementopens a receiving space penetrating through a rear surface of the firstheat-conducting element. The heat-conducting pipe is received in thereceiving space, and the heat-conducting pipe is attached between thebottom surface of the upper cover and the first heat-conducting element.The heat-conducting pipe extends rearward through a rear end of thereceiving space. The circuit board is mounted in the upper cover andcontacts with the second heat-conducting element. The lower cover ismounted to the upper cover, and the heat-conducting element, theheat-conducting pipe and the circuit board are surrounded between theupper cover and the lower cover.

Another object of the present invention is to provide a plug assembly.The plug assembly includes an upper cover, a first heat-conductingelement, a second heat-conducting element, a heat-conducting pipe, acircuit board, and a lower cover mounted to the upper cover. A top ofthe upper cover is equipped with a plurality of heat dissipation fins.The first heat-conducting element is equipped on a bottom surface of theupper cover. The second heat-conducting element is fastened to a bottomsurface of the first heat-conducting element. The heat-conducting pipeis mounted to the bottom surface of the upper cover. A front end of theheat-conducting pipe is covered by and soldered to one side of the firstheat-conducting element, so the front end of the heat-conducting pipe isattached between the bottom surface of the upper cover and the firstheat-conducting element. A rear end of the heat-conducting pipe isattached to the bottom surface of the upper cover. The circuit board ismounted in the upper cover, and the circuit board is matched with andcontacts with the second heat-conducting element.

Another object of the present invention is to provide a plug assembly.The plug assembly includes an upper cover, a first heat-conductingelement, a second heat-conducting element, a heat-conducting pipe, acircuit board and a lower cover. A top of the upper cover is equippedwith a plurality of heat dissipation fins. The first heat-conductingelement is equipped on a bottom surface of the upper cover. The secondheat-conducting element is fastened to a bottom surface of the firstheat-conducting element. A front end of the heat-conducting pipe isattached between the bottom surface of the upper cover and the firstheat-conducting element, and a rear end of the heat-conducting pipe isattached to the bottom surface of the upper cover. The circuit board ismounted in the upper cover, and the circuit board is matched with andcontacts with the second heat-conducting element. The circuit boardopens at least one perforation. The lower cover is mounted to the uppercover. At least one fastening portion is protruded from at least one ofthe lower cover and the upper cover, and the at least one fasteningportion passes through the at least one perforation and contacts withthe at least one of the lower cover and the upper cover.

As described above, the second heat-conducting element fastened to thebottom surface of the first heat-conducting element of the plug assemblycontacts with the circuit board, so that thermal energies of the circuitboard are conducted to the heat-conducting element and theheat-conducting pipe through the second heat-conducting element, and thethermal energies of the circuit board are conducted through the uppercover to a surface of the lower cover and the upper cover of the plugassembly and the plurality of the heat dissipation fins. Thus, the plugassembly has a better heat conduction effect so as to improve a heatdissipation efficiency.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will be apparent to those skilled in the art byreading the following description, with reference to the attacheddrawings, in which:

FIG. 1 is a perspective view of a plug assembly in accordance with apreferred embodiment of the present invention;

FIG. 2 is an exploded perspective view of the plug assembly of FIG. 1;

FIG. 3 is an enlarged view of an encircled portion III of the plugassembly of FIG. 2;

FIG. 4 is a partially perspective view of the plug assembly of FIG. 2;

FIG. 5 is a plan view of a circuit board of the plug assembly of FIG. 2;and

FIG. 6 is a cross-section view of the plug assembly along a line VI-VIof FIG. 1.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

With reference to FIG. 1 to FIG. 3, a plug assembly 100 in accordancewith a preferred embodiment of the present invention is shown. The plugassembly 100 with a heat dissipation function is a QSFP (Quad SmallForm-factor Pluggable) interface. The plug assembly 100 adapted forbeing assembled in a switcher (not shown) or a router (not shown),includes a lower cover 1, an upper cover 2 and a circuit board 4.

With reference to FIG. 2, FIG. 3 and FIG. 4, the lower cover 1 opens aplurality of lower fixing holes 11 vertically penetrating through thelower cover 1. The plug assembly 100 further includes a plurality offixing elements 111. Two outer side surfaces of the lower cover 1 arerecessed inward to form two lower fixing slots 12 opposite to eachother. Rears of two inner side walls of the two lower fixing slots 12are recessed inward to form two first lower buckling grooves 121opposite to each other. Fronts of the two inner side walls of the twolower fixing slots 12 are recessed inward to form two second lowerbuckling grooves 122 opposite to each other. A rear end of a top surfaceof the lower cover 1 is recessed downward to form an arc-shaped lowerrecess 13.

The upper cover 2 is mounted on the lower cover 1, so the lower cover 1is mounted to the upper cover 2. A rear end of a top of the upper cover2 protrudes upward to form a protruding stage 21. The rear end of thetop of the upper cover 2 is equipped with a plurality of heatdissipation fins 211. The plurality of the heat dissipation fins 211assists for dissipating heat. The plurality of the heat dissipation fins211 are distributed on the protruding stage 21. The plurality of theheat dissipation fins 211 have a plurality of cylindrical portions 212.The plurality of the cylindrical portions 212 facilitate a material flowof the upper cover 2 in a process of manufacturing the upper cover 2 andalso increasing a heat dissipation area of the upper cover 2. In thispreferred embodiment of the present invention, the rear end of the topof the upper cover 2 is equipped with seven heat dissipation fins 211,and each of the heat dissipation fins 211 has two cylindrical portions212. The plurality of the heat dissipation fins 211 are extended alongan elongated direction of the plug assembly 100. In this case, each ofthe plurality of the heat dissipation fins 211 has the two cylindricalportions 212. The two cylindrical portions 212 of one of the heatdissipation fins 211 and the two cylindrical portions 212 of anotherheat dissipation fin 211 next to the one of the heat dissipation fins211 are staggered. Front cylindrical portions 212 of odd-numbered heatdissipation fins 211 are in alignment with one another, and rearcylindrical portions 212 of the odd-numbered heat dissipation fins 211are in alignment with one another. Front cylindrical portions 212 ofeven-numbered heat dissipation fins 211 are in alignment with oneanother, and rear cylindrical portions 212 of the even-numbered heatdissipation fins 211 are in alignment with one another.

The plug assembly 100 further includes a heat-conducting element 22. Theupper cover 2 is equipped with the heat-conducting element 22. Theheat-conducting element 22 includes a first heat-conducting element 223equipped on a bottom surface of the upper cover 2, and a secondheat-conducting element 221 arranged and fastened to a bottom surface ofthe first heat-conducting element 223. A top of the firstheat-conducting element 223 opens a receiving space 222 penetratingthrough a rear surface of the first heat-conducting element 223. In thispreferred embodiment of the present invention, the first heat-conductingelement 223 is a copper piece. The second heat-conducting element 221 isa thermal grease or a heat dissipation patch.

With reference to FIG. 2, FIG. 3 and FIG. 4 again, the plug assembly 100further includes a heat-conducting pipe 23 mounted to the bottom surfaceof the upper cover 2. A front end of the heat-conducting pipe 23 isreceived in the receiving space 222, and the heat-conducting pipe 23 islocated and attached between the bottom surface of the upper cover 2 andthe first heat-conducting element 223. The heat-conducting pipe 23extends rearward through a rear end of the receiving space 222. Thefront end of the heat-conducting pipe 23 is covered by and soldered toone side of the first heat-conducting element 223, so the front end ofthe heat-conducting pipe 23 is attached between the bottom surface ofthe upper cover 2 and the first heat-conducting element 223, a rear endof the heat-conducting pipe 23 is attached to the bottom surface of theupper cover 2. In this preferred embodiment of the present invention,the heat-conducting pipe 23 is a copper pipe. A lower portion of theupper cover 2 opens a plurality of upper fixing holes 24 penetratingthrough the bottom surface of the upper cover 2. The plurality of theupper fixing holes 24 are corresponding to the plurality of the lowerfixing holes 11, respectively. When the upper cover 2 is assembled onthe lower cover 1, each of the plurality of the fixing elements 111passes through one of the plurality of the lower fixing holes 11 and oneof the plurality of the upper fixing holes 24 corresponding to the oneof the plurality of the lower fixing holes 11 so as to fasten the uppercover 2 to the lower cover 1. The heat-conducting element 22, theheat-conducting pipe 23 and the circuit board 4 are surrounded betweenthe upper cover 2 and the lower cover 1.

Two outer side surfaces of the upper cover 2 are recessed inward to formtwo upper fixing slots 25 opposite to each other and corresponding tothe two lower fixing slots 12, respectively. The two upper fixing slots25 are combined with the two lower fixing slots 12 to form two fixingslots 6, respectively. Rears of two inner side walls of the two upperfixing slots 25 are recessed inward to form two first upper bucklinggrooves 251 opposite to each other and corresponding to the two firstlower buckling grooves 121 respectively. Fronts of the two inner sidewalls of the two upper fixing slots 25 are recessed inward to form twosecond upper buckling grooves 252 opposite to each other andcorresponding to the two second lower buckling grooves 122 respectively.Bottom surfaces of rears of two sides of the upper cover 2 are concavedupward to form two accommodating grooves 28. The plug assembly 100further includes two resilient elements 7 accommodated in the twoaccommodating grooves 28, outer sides of the two accommodating grooves28 open two notches 281 penetrating through middles of the outer sidesof the two accommodating grooves 28. In this preferred embodiment of thepresent invention, each of the two resilient elements 7 is a spring.Bottom surfaces of fronts of the two sides of the upper cover 2 areconcaved upward to form two restricting slots 27, respectively. Twofacing inner side walls of the two restricting slots 27 protrude inwardinto the two restricting slots 27 to form two wedging blocks 271. A rearend of the bottom surface of the upper cover 2 is recessed upward toform an upper recess 26 corresponding to the lower recess 13. When theupper cover 2 is assembled on the lower cover 1, the upper recess 26 andthe lower recess 13 are combined into an insertion hole 5. An externalcable (not shown) may pass through the insertion hole 5 to be connectedwith the circuit board 4 of the plug assembly 100.

With reference to FIG. 1 to FIG. 4, the plug assembly 100 furtherincludes a receding element 3, the receding element 3 has an invertedU-shaped base portion 301, and two fixing arms 302 extended frontwardfrom two free ends of the base portion 301, the two fixing arms 302 arefixed in the two fixing slots 6, respectively. The base portion 301rides on a rear end portion of the upper cover 2 and is arranged behindthe plurality of the heat dissipation fins 211. Tops of the two fixingarms 302 protrude upward to form two upper buckling portions 31. Bottomsof the two fixing arms 302 protrude downward to form two lower bucklingportions 32. The two upper buckling portions 31 are corresponding to andbuckled in the two first upper buckling grooves 251, respectively. Thetwo lower buckling portions 32 are corresponding to and buckled in thetwo first lower buckling grooves 121, respectively. Two free ends of thetwo fixing arms 302 are connected with two buckling blocks 33 extendingvertically, upper portions of the two buckling blocks 33 are buckled inthe two second upper buckling grooves 252, respectively, and lowerportions of the two buckling blocks 33 are buckled in the two secondlower buckling grooves 122, respectively. Middles of fronts of the twobuckling blocks 33 are connected with two resisting portions 34 archedoppositely for facilitating withdrawing the plug assembly 100 from theswitcher or the router. The two resisting portions 34 are received inthe two second upper buckling grooves 252, respectively. The two fixingarms 302 are punched inward towards each other to form two abuttingblocks 35. The two abutting blocks 35 pass through the two notches 281and are assembled in the two accommodating grooves 28, and the twoabutting blocks 35 abut against the two resilient elements 7,respectively. The two abutting blocks 35 abut against free ends of thetwo resilient elements 7, respectively. A rear end of the base portion301 is connected with a pulling ring 36.

With reference to FIG. 1 to FIG. 6, the circuit board 4 is mounted inthe upper cover 2, and the circuit board 4 is matched with and contactswith the second heat-conducting element 221. The circuit board 4 has aheat emitting portion 45 matched with and contacts with the secondheat-conducting element 221. Two sides of the circuit board 4 arerestricted in the two restricting slots 27, respectively. The circuitboard 4 opens two wedging grooves 41 penetrating through two sidesurfaces of the circuit board 4. The two wedging blocks 271 are wedgedin the two wedging grooves 41, respectively, so that the circuit board 4is assembled in the upper cover 2. The two sides of the circuit board 4have two first contact portions 42 exposed outside, and a middle of atop surface of the circuit board 4 has a plurality of second contactportions 43. The two first contact portions 42 contact with the lowercover 1 and the upper cover 2. The plurality of the second contactportions 43 contact with the second heat-conducting element 221. The twofirst contact portions 42 are copper foils of the circuit board 4. Topsof the two first contact portions 42 are exposed to a top surface of thecircuit board 4, and bottoms of the two first contact portions 42 areexposed to the bottom surface of the circuit board 4. The plurality ofthe second contact portions 43 are a plurality of circular copper foilsformed on one surface of the circuit board 4. In this preferredembodiment of the present invention, the plurality of the circularcopper foils are formed on the bottom surface of the circuit board 4.

The circuit board 4 opens at least one perforation 44. The plug assembly100 further includes at least one fastening portion 441. The at leastone fastening portion 441 is protruded from at least one of the lowercover 1 and the upper cover 2, and the at least one fastening portion441 passes through the at least one perforation 44 and contacts with theat least one of the lower cover 1 and the upper cover 2. In thispreferred embodiment of the present invention, at least one portion of atop of the lower cover 1 protrudes upward to form the at least onefastening portion 441, and the at least one fastening portion 441 passesthrough the at least one perforation 44 and contacts with the uppercover 2. In another preferred embodiment of the present invention, theat least one fastening portion 441 is protruded downward from at leastone portion of a bottom of the upper cover 2, and the at least onefastening portion 441 passes through the at least one perforation 44 andcontacts with the lower cover 1.

When the plug assembly 100 is assembled in the switcher or the router,two sides of the lower cover 1 and the upper cover 2 are fastened by twoclamping portions (not shown) of the switcher or the router to make theplug assembly 100 connected with the switcher or the router. When theplug assembly 100 is withdrawn from the switcher or the router, thepulling ring 36 is pulled rearward, because the two sides of the lowercover 1 and the upper cover 2 have no way of moving on account of thetwo sides of the lower cover 1 and the upper cover 2 being fastened bythe two clamping portions of the switcher or the router, at the moment,the two abutting blocks 35 press rearward the two resilient elements 7,and simultaneously, the two resilient elements 7 generate forwardresilient forces to abut against the two abutting blocks 35,respectively. When the pulling ring 36 is kept being pulled rearward,because the two abutting blocks 35 are affected by the resilient forcesof the two resilient elements 7 to have no way of being kept movingrearward, two sides of the receding element 3 are made to expand, sothat the two resisting portions 34 prop the two clamping portions tomake the two clamping portions opened, the plug assembly 100 is able tobe withdrawn from the switcher or the router.

When the plug assembly 100 is assembled and works in the switcher or therouter, the circuit board 4 emits the heat due to a flow of electriccurrents, at the moment, the two first contact portions 42 are incontact with the lower cover 1 and the upper cover 2, the plurality ofthe second contact portions 43 are in contact with the secondheat-conducting element 221. Thus, thermal energies of the circuit board4 are conducted to the heat-conducting element 22 and theheat-conducting pipe 23 through the second heat-conducting element 221,so that the thermal energies of the circuit board 4 are conductedthrough the upper cover 2 to a surface of the lower cover 1 and theupper cover 2 of the plug assembly 100 and the plurality of the heatdissipation fins 211. The thermal energies of the circuit board 4 may beconducted to the lower cover 1 and the upper cover 2 to reach an averagetemperature by virtue of the at least one fastening portion 441 passingthrough the at least one perforation 44. The at least one perforation44, and the increased two first contact portions 42 and the plurality ofthe second contact portions 43 of the circuit board 4 make the plugassembly 100 have a better heat conduction effect. The surface of thelower cover 1 and the upper cover 2 of the plug assembly 100 is incontact with an inner wall of the switcher or the router to conductthermal energies of the circuit board 4 to the switcher or the router,and a fan (not shown) of the switcher or the router extracts externalair into the switcher or the router, and a forced convection between theplurality of the heat dissipation fins 211 of the switcher or the routerand the external air to achieve a heat dissipation effect.

As described above, the second heat-conducting element 221 fastened tothe bottom surface of the first heat-conducting element 223 of the plugassembly 100 contacts with the circuit board 4, so that the thermalenergies of the circuit board 4 are conducted to the heat-conductingelement 22 and the heat-conducting pipe 23 through the secondheat-conducting element 221, and the thermal energies of the circuitboard 4 are conducted through the upper cover 2 to the surface of thelower cover 1 and the upper cover 2 of the plug assembly 100 and theplurality of the heat dissipation fins 211. Thus, the plug assembly 100has the better heat conduction effect so as to improve a heatdissipation efficiency.

What is claimed is:
 1. A plug assembly, comprising: an upper cover, arear end of a top of the upper cover being equipped with a plurality ofheat dissipation fins; a heat-conducting element including a firstheat-conducting element equipped on a bottom surface of the upper cover,and a second heat-conducting element fastened to a bottom surface of thefirst heat-conducting element, a top of the first heat-conductingelement opening a receiving space penetrating through a rear surface ofthe first heat-conducting element; a heat-conducting pipe received inthe receiving space, and the heat-conducting pipe being attached betweenthe bottom surface of the upper cover and the first heat-conductingelement, the heat-conducting pipe extending rearward through a rear endof the receiving space; a circuit board mounted in the upper cover andcontacting with the second heat-conducting element; and a lower covermounted to the upper cover, and the heat-conducting element, theheat-conducting pipe and the circuit board being surrounded between theupper cover and the lower cover.
 2. The plug assembly as claimed inclaim 1, wherein the plurality of the heat dissipation fins have aplurality of cylindrical portions, the plurality of the cylindricalportions facilitate a material flow of the upper cover in a process ofmanufacturing the upper cover and increasing a heat dissipation area ofthe upper cover.
 3. The plug assembly as claimed in claim 1, wherein thefirst heat-conducting element is a copper piece.
 4. The plug assembly asclaimed in claim 1, wherein the second heat-conducting element is athermal grease.
 5. The plug assembly as claimed in claim 1, wherein thesecond heat-conducting element is a heat dissipation patch.
 6. The plugassembly as claimed in claim 1, wherein the heat-conducting pipe is acopper pipe.
 7. The plug assembly as claimed in claim 1, furthercomprising a plurality of fixing elements, the lower cover opening aplurality of lower fixing holes vertically penetrating through the lowercover, a lower portion of the upper cover opening a plurality of upperfixing holes penetrating through the bottom surface of the upper cover,the plurality of the upper fixing holes being corresponding to theplurality of the lower fixing holes, respectively, when the upper coveris assembled on the lower cover, each of the plurality of the fixingelements passing through one of the plurality of the lower fixing holesand one of the plurality of the upper fixing holes corresponding to theone of the plurality of the lower fixing holes so as to fasten the uppercover to the lower cover.
 8. The plug assembly as claimed in claim 1,wherein a rear end of a top surface of the lower cover is recesseddownward to form a lower recess, a rear end of the bottom surface of theupper cover is recessed upward to form an upper recess corresponding tothe lower recess, when the upper cover is assembled on the lower cover,the upper recess and the lower recess are combined into an insertionhole.
 9. The plug assembly as claimed in claim 1, wherein two outer sidesurfaces of the lower cover are recessed inward to form two lower fixingslots opposite to each other, two outer side surfaces of the upper coverare recessed inward to form two upper fixing slots opposite to eachother and corresponding to the two lower fixing slots respectively, thetwo upper fixing slots are combined with the two lower fixing slots toform two fixing slots, respectively, the plug assembly further includesa receding element, the receding element has an inverted U-shaped baseportion riding on a rear end portion of the upper cover and arrangedbehind the plurality of the heat dissipation fins, and two fixing armsextended frontward from two free ends of the base portion, the twofixing arms are fixed in the two fixing slots, respectively, a rear endof the base portion is connected with a pulling ring.
 10. The plugassembly as claimed in claim 9, wherein rears of two inner side walls ofthe two lower fixing slots are recessed inward to form two first lowerbuckling grooves opposite to each other, rears of two inner side wallsof the two upper fixing slots are recessed inward to form two firstupper buckling grooves opposite to each other and corresponding to thetwo first lower buckling grooves respectively, tops of the two fixingarms protrude upward to form two upper buckling portions, bottoms of thetwo fixing arms protrude downward to form two lower buckling portions,the two upper buckling portions are corresponding to and buckled in thetwo first upper buckling grooves, respectively, the two lower bucklingportions are corresponding to and buckled in the two first lowerbuckling grooves, respectively.
 11. The plug assembly as claimed inclaim 9, wherein fronts of two inner side walls of the two lower fixingslots are recessed inward to form two second lower buckling grooves,fronts of two inner side walls of the two upper fixing slots arerecessed inward to form two second upper buckling grooves opposite toeach other and corresponding to the two second lower buckling groovesrespectively, two free ends of the two fixing arms are connected withtwo buckling blocks extending vertically, upper portions of the twobuckling blocks are buckled in the two second upper buckling grooves,respectively, and lower portions of the two buckling blocks are buckledin the two second lower buckling grooves, respectively.
 12. The plugassembly as claimed in claim 11, wherein middles of fronts of the twobuckling blocks are connected with two resisting portions archedoppositely for facilitating withdrawing the plug assembly.
 13. The plugassembly as claimed in claim 9, wherein the two fixing arms are punchedinward towards each other to form two abutting blocks, bottom surfacesof rears of two sides of the upper cover are concaved upward to form twoaccommodating grooves, the plug assembly further includes two resilientelements accommodated in the two accommodating grooves, outer sides ofthe two accommodating grooves open two notches penetrating throughmiddles of the outer sides of the two accommodating grooves, the twoabutting blocks pass through the two notches and are assembled in thetwo accommodating grooves, and the two abutting blocks abut against thetwo resilient elements, respectively.
 14. The plug assembly as claimedin claim 13, wherein each of the two resilient elements is a spring. 15.The plug assembly as claimed in claim 1, wherein bottom surfaces offronts of two sides of the upper cover are concaved upward to form tworestricting slots, respectively, two facing inner side walls of the tworestricting slots protrude inward into the two restricting slots to formtwo wedging blocks, two sides of the circuit board are restricted in thetwo restricting slots, respectively, the circuit board opens two wedginggrooves penetrating through two side surfaces of the circuit board, thetwo wedging blocks are wedged in the two wedging grooves, respectively,so that the circuit board is assembled in the upper cover.
 16. The plugassembly as claimed in claim 1, wherein the circuit board opens at leastone perforation, the plug assembly further includes at least onefastening portion protruded from at least one of the lower cover and theupper cover, and the at least one fastening portion passes through theat least one perforation and contacts with the at least one of the lowercover and the upper cover.
 17. A plug assembly, comprising: an uppercover, a top of the upper cover being equipped with a plurality of heatdissipation fins; a first heat-conducting element equipped on a bottomsurface of the upper cover; a second heat-conducting element fastened toa bottom surface of the first heat-conducting element; a heat-conductingpipe mounted to the bottom surface of the upper cover, a front end ofthe heat-conducting pipe being covered by and soldered to one side ofthe first heat-conducting element, so the front end of theheat-conducting pipe being attached between the bottom surface of theupper cover and the first heat-conducting element, a rear end of theheat-conducting pipe being attached to the bottom surface of the uppercover; a circuit board mounted in the upper cover, and the circuit boardbeing matched with and contacting with the second heat-conductingelement; and a lower cover mounted to the upper cover.
 18. A plugassembly, comprising: an upper cover, a top of the upper cover beingequipped with a plurality of heat dissipation fins; a firstheat-conducting element equipped on a bottom surface of the upper cover;a second heat-conducting element fastened to a bottom surface of thefirst heat-conducting element; a heat-conducting pipe, a front end ofthe heat-conducting pipe being attached between the bottom surface ofthe upper cover and the first heat-conducting element, and a rear end ofthe heat-conducting pipe being attached to the bottom surface of theupper cover; a circuit board mounted in the upper cover, and the circuitboard being matched with and contacting with the second heat-conductingelement, the circuit board opening at least one perforation; and a lowercover mounted to the upper cover, at least one fastening portion beingprotruded from at least one of the lower cover and the upper cover, andthe at least one fastening portion passing through the at least oneperforation and contacting with the at least one of the lower cover andthe upper cover.